Nutrition Final Review

Intracellular fluid

Fluid found within body cells.

Plasma

Fluid component of blood in intravascular space.

Interstitial fluid

Fluid between body cells.

Negatively charged electrolyte

Electrolyte with a negative charge, e.g., chloride.

Extracellular ions

Common ions outside cells, mainly sodium and chloride.

Intracellular ions

Common ions inside cells, mainly potassium and phosphate.

Common body solvent

Water, essential for biological processes.

Hydrophobic substances

Substances that repel water, e.g., lipids.

Aldosterone function

Signals kidneys to retain sodium and chloride.

Antidiuretic hormone (ADH) function

Stimulates kidneys to reabsorb water.

ADH release site

Released from the hypothalamus.

Kidneys' role

Regulate blood volume and blood pressure.

Active vasoconstrictor

Angiotensin II in the renin-angiotensin system.

Aldosterone production site

Produced by the adrenal glands.

Sweating purpose

Regulate body temperature through evaporative cooling.

Cell swelling consequence

Occurs if intracellular electrolyte concentration is high.

Thirst mechanism stimulus

Increased solute concentration in the blood.

Fluid intake control region

Hypothalamus regulates thirst and fluid intake.

Insensible water loss

Water lost through perspiration and respiration.

Diuretic example

Alcohol increases urine production.

High sodium diet effect

Associated with hypertension.

Common extracellular ions

Sodium and chloride are predominant.

Common intracellular ions

Potassium and phosphate are predominant.

AI for sodium

Adequate Intake is 2.4 g/day for adults.

Sodium absorption site

Most sodium is absorbed in the small intestine.

Hyponatremia

Low sodium due to insufficient intake and overhydration.

Best potassium source

Legumes and vegetables provide optimal potassium.

Phosphorus storage

Majority stored in bones of the body.

Phosphorus absorption enhancer

Vitamin D enhances phosphorus absorption efficiency.

Vulnerable to dehydration

Infants and elderly are most at risk.

Dehydration classification

Classified by percentage of weight loss from fluids.

Overhydration causes

Common in individuals with kidney retention issues.

Urine color when hydrated

Well-hydrated urine appears clear to pale yellow.

Heat stroke

Fatal condition from failure of heat regulation.

Optimal blood pressure

Systolic <120 mmHg and diastolic <80 mmHg.

Blood pressure improvement

Alcohol consumption does not improve blood pressure.

High risk for hypertension

African Americans have elevated hypertension risk.

Dissolved substances

Solutes are substances dissolved in fluids.

Weight gain contributor

Soft drinks significantly contribute to obesity rise.

Diuretic

Substance that increases urine fluid loss.

Action potential trigger

Sodium influx triggers an action potential in nerves.

Fluid loss mechanism

Diuretics increase fluid loss via urine.

Sodium intake recommendation

Recommended sodium intake is 2.4 g/day.

Dehydration symptoms

Symptoms include thirst and decreased urine output.

Potassium-rich foods

Nuts and seeds also provide potassium.

Osmosis

Water movement from low to high solute concentration.

Acid-base balance systems

Lungs, kidneys, and blood buffers regulate pH.

Best drinking water source

Tap water is preferred for most Americans.

Reduction

Gaining electrons by an atom in metabolism.

Free radicals

Atoms with unpaired electrons, often harmful.

Antioxidants

Substances that neutralize free radicals.

Glutathione peroxidase

Enzyme that reduces hydrogen peroxide to water.

Dietary antioxidants

Major source of antioxidants for the body.

Electron donation

Antioxidants stabilize free radicals by donating electrons.

Cancer

Disease linked to free radical damage.

Reactive oxygen species (ROS)

Oxygen molecules that become free radicals.

Free radical

Unstable atom with an unpaired electron.

Antioxidant stabilization

Antioxidants donate electrons to free radicals.

Vitamin E destruction

Heating oils reduces vitamin E content.

Vitamin C

Regenerates oxidized vitamin E in the body.

Vitamin E storage

90% of vitamin E is stored in adipose tissue.

Function of vitamin E

Protects cell membranes from oxidative damage.

Sensible water loss

Water loss through urine and sweat.

Blood buffers

Substances that help maintain pH balance.

Prooxidant

Substance that promotes oxidative damage.

Mineralization

Process of adding minerals to tissues.

Phospholipids

Largest class of antioxidants in cell membranes.

Antioxidant vitamins

Vitamins that protect against oxidative stress.

Vitamin E

Protects cell membranes from oxidation.

Vitamin C

Regenerates vitamin E by donating an electron.

Vitamin C deficiency

Causes scurvy, characterized by bleeding gums.

Collagen

Structural protein formed with vitamin C assistance.

Anticoagulants

Medications that can cause bleeding with vitamin E.

Fat malabsorption

Leads to vitamin E deficiency.

RDA increase for vitamin C

Smoking cigarettes raises vitamin C requirements.

Best source of vitamin C

Citrus fruits are highest in vitamin C.

Symptoms of vitamin C megadose

Nausea and diarrhea can occur.

Beta-carotene

Carotenoid converted to retinol in the body.

Carotenoids

Support immune system and antioxidant functions.

Bioavailable beta-carotene

Greatest in 1 cup lightly cooked carrots.

Catalase

Enzyme that eliminates hydrogen peroxide using manganese.

Superoxide dismutase

Antioxidant enzyme using copper and zinc.

Vitamin C absorption

Increased by taking iron with orange juice.

Vitamin E in skincare

Prevents oxidation in oil-based products.

Vitamin E and bone health

Critical for postmenopausal bone density.

Vitamin E in development

Important for fetal and childhood growth.

Sources of vitamin C

Rich in green and red peppers.

Antioxidant enzyme system

Includes copper, zinc, and manganese.

Retinoic acid

Most significant retinoid in physiological roles.

Vitamin A

Essential nutrient important for vision and immunity.

Vitamin E supplements

Can interact negatively with cholesterol-lowering medications.

Vitamin A

Essential for vision and eye health.

Fat-soluble vitamin

Can cause toxicity if consumed excessively.

Xerophthalmia

Irreversible blindness from vitamin A deficiency.

Night blindness

Condition caused by vitamin A deficiency.

Carcinogens

Agents that can cause cancer.

Promotion

Stage in cancer development with cell division.

Cancer risk reduction

Associated with increased fruits and vegetables intake.

Saturated fats

High intake linked to increased cancer risk.

Second-hand smoke

No risk-free level of exposure exists.